[Colorectal polyps: update on diagnosis]. / Pólipos colorectales: actualización en el diagnóstico.

Histological diagnosis determines the clinical behavior of colorectal polyps. Recently new types of polyps have been described and the classification has become wider and more complex. Our aim is update the current concepts in the knowledge of colorectal polyps.

Cowden's syndrome affecting the mouth, gastrointestinal, and central nervous system: a case report and review of the literature.

Cowden's syndrome (CS) is a rare genodermatosis, of autosomal dominant inheritance and variable phenotype, principally characterized by the formation of hamartomas in various organs, including skin, thyroid, breast, brain, and gastrointestinal tract and by the increased risk for the development of malignancy. The present report details the features of a very rare presentation of Cowden's syndrome affecting not only the mouth and gastrointestinal mucosa but also the central nervous system.

Peutz-Jeghers syndrome in a 14-year-old boy: case report and review of the literature.

Peutz-Jeghers syndrome (PSJ) is a relatively rare but well-recognized condition, with a prevalence of approximately one in 120,000 births in the USA. It is generally inherited as an autosomal dominant trait, although 35% of cases are new mutations. This disorder is characterized by melanocytic macules on the hands, feet, peri-oral skin and oral mucosa, and multiple gastrointestinal hamartomatous polyps. People with PSJ have an increased risk for developing a variety of malignant tumours. The aim of the present study was to report one case of PSJ in a 14-year-old boy with mucocutaneous pigmentation associated with duodenal hamartomatous polyps.

Inflammatory fibroid polyp: an immunohistochemical study

RACIONAL: O pólipo inflamatório fibróide é uma lesão localizada que se origina na submucosa do trato gastrointestinal, mais freqüentemente do estômago. Embora se acredite que represente condição reativa e não neoplásica, sua histogênese permanece controversa. OBJETIVO: Estudar o pólipo inflamatório fibróide por imunoistoquímica na tentativa de contribuir para o entendimento de sua histogênese. PACIENTES AND MÉTODOS: Foram estudados nove casos por imunoistoquímica usando-se um painel de anticorpos contra actina de músculo liso, vimentina, proteína S-100, fator VIII e macrófago (HAM-56). RESULTADOS: Houve um padrão difuso de coloração nas células fusiformes, fortemente positivo para vimentina. Um padrão focal de positividade para actina de músculo liso foi observado nessas células. O estudo revelou reação heterogênea com HAM-56. Nas áreas edematosas, as células positivas para HAM-56 mostraram citoplasma volumoso e núcleos reniformes. Nas áreas ricamente celulares, as células positivas para HAM-56 apresentaram citoplasma fusiforme. As reações para S-100 e fator VIII foram negativas nos elementos proliferantes. CONCLUSÕES: O presente estudo imunoistoquímico afasta a hipótese de natureza neural ou vascular da lesão. A forte positividade para vimentina em todos os casos sugere um componente principal de células fusiformes, melhor reconhecidas como fibroblastos. Estes resultados favoreceriam a existência de um espectro de padrões morfológicos e imunoistoquímicos, indicando, possivelmente, fases evolutivas de uma reação inflamatória.

Gastric and small intestinal lesions after partial stomach resection with Billroth II or Roux-en-Y reconstruction in the rat.

The evolution and phenotypic expression of mucosal lesions of the gastric stump were investigated in male rats submitted to gastric resection with reconstruction by the Billroth II technique (BII with biliopancreatic reflux, BPR) or by the Roux-en-Y procedure (without BPR). Animals were studied at 24, 36, 54 and 64 weeks after surgery and the phenotypic expression of lesions analysed using routine hematoxylin and eosin staining, immunohistochemical staining for pepsinogen isoenzyme 1 and histochemical procedures for mucins (paradoxical concanavalin A, galactose oxidase Schiff (GOS) and sialidase GOS reactions). BPR was found to be responsible for the formation of adenomatous hyperplasia (AH), increasing in incidence and size with time, since the Roux-en-Y procedure failed to induce the gastric stump lesions observed after BII reconstruction. AHs always occurred in the transition of the gastrojejunal junction, a site offering special conditions for BPR influence, and were classified as gastric (G), intestinal (I) and G+I types according to their phenotypic expression. No pure I type AH was diagnosed at any time point. The G and G+I types developed at approximately equal incidences (i.e., G type 7/17, G+I type 10/17 at the 64th week). It was suggested that both gastric and intestinal mucosal elements were stimulated to proliferate by BPR, with the gastric mucosa tending to demonstrate AH. Intestinal type components of AH were found adjacent to the jejunum and not at the stomach margin, indicating an origin from intestinal mucosa. No metaplasia of the gastric mucosa was observed in any animal after partial gastric resection. In 101 rats submitted to the BII procedure, 5 mucinous adenocarcinomas were eventually diagnosed, mostly located in the subserosa of the gastrojejunal junction. All carcinomas expressed the phenotype of cells of the small intestine. Evidence of malignant transformation within the gastric components of AH was not observed even at the 64th week. In conclusion, all lesions induced by BPR in the rat remnant stomach are benign, and the few true cancers that arise in association are derived from the small intestine.

Pólipos de colon y recto / Colon and rectum polyps

Se llevó a cabo una investigación prospectiva sobre pólipos de colon y recto; se integraron dos grupos, el primero considerado como de estudio correspondió a 20 enfermos portadores de la enfermedad. El segundo, lo integraron 8 sujetos sanos. El objetivo fue la de reafirmar o eliminar algunos conocimientos actuales sobre su origen, diagnóstico y tratamiento. El hallazgo encontrado con respecto a la dieta rica en carbohidratos puede ser coincidental; pero al igual que en el carcinoma, se puede sospechar que existe una relación entre ingesta de azúcares refinados y la aparición de pólipos colorectales. Los niveles de IgG sérica se encontraron disminuidos en el grupo de estudio con valor medio de 1148.7 + ou - 473.6, ésto proporcionó una p=0.001. En neoplasias malignas de colon también se demostraron disminución de los niveles de IgG, lo que señala, factores inhibitorios humorales en la linfoblastogénesis y en la producción de inmunoglobulinas. Se precisó que la endoscopía es el método de elección para el diagnóstico de pólipos en colon y recto, en nuestro trabajo se observó importante diferencia al ser comparada con el colon por enema, doble contraste. El diagnóstico temprano y el tratamiento oportuno de esas neoplasias proporcionaron magníficos resultados en dos enfermos que les fueron extraídos de ámpula rectal, pólipos con carcinoma in-situ. Se demostró que la polipectomía transendoscópica tiene más ventajas que el tratamiento quirúrgico. El análisis histológico informó predominio de pólipos adenomatosos

The epidemiology of colorectal polyps: prevalence in New Orleans and international comparisons.

Based on a study of the prevalence of intestinal polyps in New Orleans and on international comparisons, the following conclusions are reached. 1) There is a close parallelism in the epidemiology of colon cancer and adenomatous polyps. Both conditions are statistically associated with respect to geography, anatomic localization, socioeconomic class, migration experience and time trends. 2) The strength of the association favors the notion of a direct, positive correlation between multiplicity, size and atypia of polyps, and cancer risk, equivalent to "dose-effect". 3) The epidemiologic findings are coherent with other biologic facts derived from clinical, morphological and experimental studies. 4) Adenomatous polyps are a good epidemiologic indicator of colon cancer risk and their presence should be helpful in advancing from studies of the epidemiology of colon cancer to the epidemiology of precursor lesions.

Pólipo inflamatorio del intestino en el niño / Intestinal inflammatory polyp in child

Se estudian 15 casos de lesiones únicas del colon y recto, que se definen en la literatura como pólipos inflamatorios, pólipos juveniles, seudopólipos, etc, con las caracteristicas histológicas en las que se entremezclan los elementos de tipo glandular con dilatación quística, células inflamatorias y un estroma de tejido conectivo variado, así como reacción ósea vista por nosotros en dos de los casos. Estos pólipos inflamatorios, generalmente son lesiones únicas, raras veces recidivan y por los conceptos vertidos no tienen carácter maligno. Suelen encontrarse alrededor de los 6 ó 7 años de edad y el síntoma predominante es el sangramiento rectal. Ellos deben diferenciarse de otras formas de pólipos que pueden traer un carácter maligno. En cuanto al mecanismo patogénico, no existe una teoría convincente para este tipo de lesión, aunque nosotros nos acercamos al planteamiento hipotético hecho por Klepinger(AU)